The figures (from non-Canon sources) indicate that Starbase 74 is approximately 3.36 times longer than Earth Spacedock and give it nearly forty times Spacedock's overall volume.

Earth Spacedock is described as approximately 3.6km in diameter and 4.6km tall[6]. Based on the size comparison using starships, Starbase 74 is approximately 12.1 kilometers in diameter and 15.5 km long (excluding the antenna towers at either end of the station, which would make the station over 18 km in overall length).

In Debates

Trekkies sometimes argue that the large scale of Starbase 74 demonstrates that the Federation has the industrial capacity to build thousands of starships per year, even though the timeframe for the construction of Starbase 74 is unknown (albeit well within the 200-year history of the Federation).

Warsies counter-argue that, regardless of the time spent building it, many of the complex systems needed for a starship -- such as mass lightening systems, warp drive, impulse engines, and other systems needed for a vessel expected to travel between star systems under its own power -- are not necessary for a space station. Warp drives, in particular, comprise a large portion of a starship's overall volume. Consequently, the construction of a space station would be, in many ways, much simpler than the construction of a starship, even if the station is very large in comparison.

In reply, Trekkies argue that the stations still possess many systems in common, such as weapons, shields, limited forms of propulsion (such as thrusters), power plants, fuel storage, etc. The systems cited, however, generally do not have the same scaling issues as main engines.

Trekkies also note that the Federation built not one but at least four of these mammoth stations. Additional stations of this class include the following: [8]

Also, a large space station of unconfirmed size was observed housing a Galaxy-class starship under construction at the Utopia Planitia Fleet Yards;[9] it's interior docking bay was virtually identical to Spacedock and Starbase 74.